The simplest way to convert a Bitmap image to JPEG is -
Open the image using MS Paint or Paint.net (the newer version of the good old MS Paint).
Go to File, click on the Save As button
When you get to this point, there will be a drop down menu for the file format. Choose JPEG and hit the Save button. There you go - you have the bitmap image in JPEG format.
Hope this helps!
how to convert bitmap image to jpeg?